The Last Project

[Mgmark]

Here it is, a C&J framed TZ750. I won’t need to build anything else after this. A pal of mine had this and realized he would never get around to building it. He has plenty of other things going on. He offered it to me so, why not? I have built and raced a 750 in the past so it is fairly familiar.
The project did come with all the big parts to build it; gas tank, seat, front fender, lots of pipes and pieces but a lot of it needs repair work. The engine is already built and ready to go. The bike is a project and needs most everything figured out. First up is decide what forks to use, then what brakes, then axles, spacers etc to make a roller.
I have a set of 40mm Forcella forks with Spondon triples, and a 36mm TX750 front end which looks a lot like the original TZ forks after some clean up of the triple clamps. The TX forks would use stock Yamaha RD/TZ type calipers that I have.
I also have a pair of stock TZ wire wheels with the bike.

[dgorms]

Wow! Might as well go out with a big BANG.........................D

[m in sc]

 

-everyone is jealous.

 

[Mgmark]

Don’t be too jealous, it ain’t gonna be cheap……

This is a mock-up pic before I got the bike.

[Mgmark]

First up is decide what forks to use. I like the 36mm TX front end because it looks almost stock, but the steering stem is too long. But then a miracle occurred and an RD steering stem is exactly the right length. So press out the TX stem and press in and weld the RD stem to the TX lower triple clamp.
The other option is the 40mm Forcella forks which are better parts than the Yamaha forks, with the adjustable trail Spondon triple clamps  They have adjustable spring compression and dampening.

[Evans Ward]

I’ll be watching this unique epic build Mark! Can’t wait to see it running and in person. 

[Mgmark]

I’ll be watching this unique epic build Mark! Can’t wait to see it running and in person. 

Hopefully it will be ready for the DG meet next year.

[oxford]

First up is decide what forks to use. I like the 36mm TX front end because it looks almost stock, but the steering stem is too long………………

The other option is the 40mm Forcella forks which are better parts than the Yamaha forks. They have adjustable spring compression and dampening.

Here’s my take on this, and for the record I tend to overthink and make stuff like this a big deal.

Since you have both, use the best ones you have which sound like the 40mm.  You aren’t doing a concourse restoration(not that the tx would work for that anyways) and in the end there are very few that will even know.  The ones that would would most likely know the TX aren’t original as well. 

If it was a factory frame and you were questioning using factory forks then the decision would be different.

[Vintagetz]

Mark,

How are you doing a long time no speak and yes I am envious... I agree with Oxford, given it's a C&J I would use the better forks.  once you get it assembled just take it to Bigley and have him do a set of pipes for you from a Swarbrick kit.

[Mgmark]

Yes, after messing about back and forth I agree the 40mm forks with Spondon triples are the way to go. They are the better parts. Of course that means making up caliper mounts to fit and axle spacers, etc but overall probably the better choice.

The bike isn’t original Yamaha so I think I can do whatever I want without hurting value. There is a story about this frame as to who had it first but since there are no frame numbers there is no way to verify any history.

The bike came with two complete sets of pipes, including an original set of D/E/F pipes, and another set in pieces. Rusty is the go-to guy to have pipes made but that is a ways down the road. A lot of other decisions need to come first.

C&J frames came out as a replacement for original A/B/C twin shock 750s so it will probably be a mix and match for what components fit are early and some later model.

[Kawtriplefreak]

I can't wait to see you work your magic on this one my friend.

[teazer]

It's official.  I hate you now.  Or loosely translated I am jealous as ......

You know it will never be half the bike of that other beauty hiding under a cover because she is modest and didn't want the new girl to feel bad.

C&J frames: I have one for a TZ250/350 and for sure, no frame number anywhere so it's impossible to be sure of any provenance.

Forks and suspension you will work out. What barrels are on that motor - 40970 would be original twin shock and 40970 or 40971 are CDE full 750cc. And if it has six port transfer port barrels (OW31 or replicas), I will be even more jealous. 

Great project.

[Mgmark]

The motor has a 40970 750cc top end with fresh plating. The cases are replacements so no numbers there. It has fresh Hoekle cranks in it. So the motor is ready to go. I’m going to run 34mm round slide Mikunis that came with it. I had Lectrons on my first 750 but all that stuff went with the bike when I sold it. The rest of the bike is just deciding what cycle parts and making everything work as a unit.

I decided to run TZ brake disks with the Spondon calipers. It should stop pretty well. I need to make caliper hangers to fit the forks.

Mark

[Mgmark]

Rear brake options: I have a small Brembo caliper and hanger, with a semi-floating disc that needs some spacers made up to work, or a stock TZ monoshock caliper hanger that uses an RD/TZ type caliper, and RD diameter brake disc. I have these parts laying around to test fit. The TZ alloy caliper and brake disc can be had to use for a correct assembly.

[teazer]

Needs an alloy caliper for sure.

Nice Spondon floating rear disk.  Had one like that on a client's Rotax powered spondon years ago

Did the 750 use an RD type large rear disk and not solid steel that the 350 came with?  I never stopped to look at a rear disk before.  I always get stuck drooling at the powerplant.

40970 are good.  Does Vince @ Fondseca still sell replica 6 transfer port barrels?